Статьи журнала - Инженерные технологии и системы
Все статьи: 2056
Статья научная
Introduction. The problem of mathematical modeling in innovative technologies is the lack of a developed general model of innovation processes. The existing approaches allow simulating innovations from any one part: political, economic (in various aspects) or describe the general structure of innovative activity. For example, innovations can be estimated such indicator as sales volume of an innovative product. However, it does not mean that there are no other indicators or they are not important. Materials and Methods. The models by L. Leydesdorf and S. Kauffman, including NK model originally used for the analysis of development of biological populations, were chosen for research of the model choice problems of the innovative integrated structure between university, the enterprise and research laboratory. Results. Modeling the innovative integrated structure between participants of process is carried out based on expert assessment of the innovative landscape for a case of the maximum interdependence. Conclusions. A brief description of modeling methods in innovative technologies is presented in this article. The general description of the problem sphere is given. The current state of researches of this problem is specified. The imitation of innovative networks development options based on the NK model at the independent strategy of participants is constructed. The case of the maximum complexity of network when all participants of an innovation are interconnected and also local and global optimum in a landscape of projects payback is considered.
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Data analysis in gamma-ray compton spectroscopy
Статья научная
Compton scattering is a technique for determining the momentum distribution of electrons in condensed matter. Therefore, in the Compton scattering experiment all the available data about the electron's initial state is contained in the distribution of the inelastically scattered radiation, i.e. the Compton profile. However, before the data can be interpreted, a series of energy dependent corrections have to be applied. In this paper, general aspects of the Compton Scattering theory are introduced. Data analysis procedure for the y-ray experiment is outlined and the sensitivity of these corrections on the quality of the final results is discussed.
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Статья научная
Introduction. The task of building a management system is to help the manager in the process of making decisions. This provides for the establishment of goals and focuses on the construction of an integrated system unlike the construction of separated subsystems. The system requirements are determined by the reduction of data and knowledge on the phenomena and process, occurring during the operation of the facility management object. Materials and Methods. The approach, used in this paper, is determined by the structure of the management systems, what is necessary to identify the main activities of the control object. The complex of functions is implemented and followed by determination of functional subsystems, which are necessary for the computerization of the control object. It should be noted that the proposed approach is a model and is suitable for developing the functional structure of only complexity. Results. As a result, a unified service system of the enterprise appears. This system includes structural units responsible for the procurement and delivery of material resources, storage and movement of material flow as a part of the technological process, and the sale of finished products. These measures together can increase the efficiency of the enterprise and give its development dynamism in a difficult situation of market competition. Discussion and Conclusion. The task of building a management system is to help the manager in the process of making decisions. This provides for the establishment of goals and focus on the construction of an integrated system unlike the construction of separated subsystems. The system requirements are determined by the reduction of data and knowledge on the phenomena and process, occurring during the operation of the facility management object.
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Статья научная
Introduction. The article deals with the effect of mexidol and melatonin in the separate and combined use, on the process of carcinogenesis of soft tissue induced by benzopyr-ene at mice. Materials and Methods. 120 mice were divided into four groups: three experimental groups of 30 mice, 30 mices are the control group on carcinogen. Animals from the all four groups were applied with benzoapyrene at a dose of 0.2 ml per mouse, 2 times a week. Results. It is found that the histological examination has showed a pattern similar to malignant fibrous histiocytoma. In the application of melatonin, the number of animals with induced tumors was 57 %, under the influence of mexidol frequency of formation of tumor nodes was 50 %. With combined use of mexidol and melatonin, the number of mice which had progressing tumor nodes was 36.6 %. Discussion and Conclusions. While induced tumor growth of soft tissue, we can identify the various stages of the morphogenesis of malignancy.
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Flow boiling heat transfer of grooved copper foam with open gap
Статья научная
Introduction. Copper foam material has various advantages. It has been proved effective in enhanced boiling heat transfer, but also increases pump power consumption. Grooved copper foam is a solution to achieve good balance between boiling heat transfer characteristics and pump power consumption. Material and Methods. Grooveless and grooved copper foam in open space was studied. Copper foam specifications comprised the combination of porosities of 70, 80 and 90%, and pore densities of 90 and 110 PPI. The grooved copper foams have two specifications: 11 and 17 grooves. The corresponding rib widths are 2 and 1 mm, with groove depth 2.9 mm and width 0.6 mm. The flow boiling experimental system of copper foam sample includes four parts: a heating water reservoir, pump, a test section, and a data acquisition system. In the test section, liquid water turns into vapor and carries the heat away from a copper block surface, and then vapor condenses into liquid water in the terminal reservoir. Results. Grooved copper foam samples presented significantly higher efficiency than grooveless ones. Grooved copper foams can increase the critical heat flux and heat transfer coefficient, compared with grooveless ones. Seventeen-grooved samples showed more excellent performance than 11-grooved ones. Visual observation disclosed that the stratified flow pattern dominated in moderate and high heat flux for grooved copper foam with open space. Covering vapor mass was more effective to be formed above 17-grooved samples, compared with 11-grooved ones. It indicated more vigorous boiling behavior occurs in 17-grooved sample. Discussion and Conclusion. The number of grooves has a significant impact on boiling heat transfer. Grooved copper foam samples present a significantly higher critical heat flux and heat transfer coefficient. Structural parameters such as porosity and pore density, play a relatively secondly role in heat transfer argumentation. Visual observation shows there exists a cyclic alternation of flow patterns: bubbly flow, annular flow and mass vapor formation for grooved samples. Forming vapor mass is more effective to be formed in 17-grooved samples, compared to 11-grooved ones. It indicates more vigorous boiling behavior occurs in 17-grooved samples.
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Gamma-ray compton spectroscopy of tungsten using 662 KeV gamma-ray radiation
Статья научная
Compton profile measurement of Tungsten polycrystalline sample has been performed with 662 KeV y-radiation from a cesium-137 source scattered at 900. The Spectrometer calibration and data corrections for the high energy experiment are discussed. The data are compared with the augmented-plane-wave (APW) band theoretical Compton profile of Tungsten. Theoretical predictions show the band theory overestimates the momentum density at low momenta and underestimates it at intermediate momenta. The discrepancies between experiment and theory were attributed to some non-local exchange-correlation effects and the spin-orbital interaction effect which were neglected in the theoretical calculation.
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Harrow with turning disc section
Статья научная
Introduction. At present, there is widely used smooth plowing, which is moldboard plowing without back ridges and deep furrows. Aim of the Article. The article deals with developing a new design of working tools for smooth soil plowing that ensure the fulfillment of the required quality of soil cultivation. Materials and Methods. Based on the analysis of existing designs, the authors developed a harrow with a turning disc section, which is characterized by increased operational reliability by reducing energy costs for its adjustment. The range of change in the approach angle of the disk working bodies is 5-45°. Results. It was found that the speed of movement and the inclination angle disks have the greatest influence on the tillage quality. To optimize the motion parameters with a turning disk section for the best smooth plowing quality, a two-factor experiment was carried out. Discussion and Conclusion. As a result, it was found that at a speed of 9.113 km/h and approach angle of working disks of 32°, the quality of tillage is maximum and amounts to 86.1%.
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Статья научная
Introduction. Recently, sandwich-structured composite materials based on honeycomb core and strong thin shells have become widespread. However, these materials are characterized by manufacturing and operational flaws such as “non-gluing” and “delamination” that is the breaking of the bonds between the shell and the honeycomb core that result in the deterioration in the mechanical, acoustic and thermal properties of the material. Aim of the Study. The study is aimed at developing effective methods for detecting flaws in gluing shell with comb core in honeycomb polymer materials.
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Improvements in broom corn harvesting process
Статья научная
Introduction. Solving the problem of harvesting broom corn (Sorghum vulgare var. technicum) with minimal expenditure of labor and resources, and high quality is possible through improving existing or developing new processes and equipment for harvesting. At the same time, the proposed new processes and equipment should ensure the reduction or complete elimination of the share of manual labor. The purpose of the work is to improve the process for harvesting of broom corn based on a complex performance criterion. Materials and Methods. The methodological basis for choosing an effective process for harvesting broom corn was the theory of efficiency of technical systems. According to it, the latter is estimated using the value of a complex criterion that includes a set of particular indicators and their relative importance. Results. It is proposed to evaluate the efficiency of the broom corn harvesting process according to a complex criterion that takes into account particular indicators and their relative importance. A developed process for harvesting broom corn includes: threshing of standing broom corn in the direct flow offset threshing chamber of a combine harvester with simultaneous mowing of the threshed plants using the combine harvester thresher; collecting the threshed and mown plants in the tractor trailer and the threshed grain in the hopper; transportation of threshed and cut plants to the place of storage; and stacking of threshed plants with drying them using active ventilation. Based on experimental studies, the values of all the studied particular indicators and their coefficients of relative importance were determined; a comprehensive performance criterion for the existing process for broom corn harvesting and the proposed process was calculated. Discussion and Conclusion. The calculated values of coefficients K* 1 and K* 2 for the existing and proposed processes for harvesting broom corn were used to determine the complex performance criterion, which is φ(Wi ) = 15.54 for the existing process and φ(Wi) = 2588.75 for the proposed one respectively. According to the complex criterion, the proposed harvesting process is more efficient than that currently used more than 160 times.
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Interdisciplinary modelling of robots using CAD/CAE technology
Статья научная
Introduction. The paper describes an interdisciplinary approach that integrates physical and virtual (3D) modelling methods and tools in a high industrial undergraduate engineering school research environment and in an industrial design. The CAD/CAE procedures were connected directly with physical modelling for robotic systems of various types: mobile robots, manipulators etc. Thus, the design problems for the robot are solved in the both environments: physical and virtual. Materials and Methods. The approach includes three separate parts: 1) SolidWorks; 2) Ar-duino, Fischertechnik and RoboRobo sets; 3) MS Visual Studio C++, COM technology SolidWorks and a POSIEX socket API (Application Program Interface). API and COM are used as the integration tools for physical and virtual parts. Corresponding Add-In or Stand-Alone applications extract the model features used for determining the necessary kinematic and dynamic parameters for robotics control. Robot webcams, sensors and feedback allow to establish a bidirectional connection between the behaviours of the 3D (virtual) and the physical models. Results. The developed virtual (3D), physics models and software for the robots represent the integrated framework used in industrial design and research process. This interdisciplinary approach is realized as project-based learning in the educational and research process and in the industrial design practice. Conclusions. The modern industry design is the interdisciplinary field with high level of integration between the disciplines. This research demonstrated that the developed integrated framework is effective for both industry design practice and engineering research.
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Статья научная
Introduction. The classical topology optimization leads to a prediction of the structural type and overall layout, and gives a rough description of the shape of the outer as well as inner boundaries of the structure. However, the probabilistic topology optimization (or reliability-based topology optimization) model leads to several reliability-based topologies with high performance levels. The objective of this work is to provide an efficient tool to integrate the reliability-based topology optimization model into free vibrated structure. Materials and Methods. The developed tool is called inverse optimum safety method. When dealing with modal analysis, the choice of optimization domain is highly important in order to be able to eliminate material taking account of the constraints of fabrication and without affecting the structure function. This way the randomness can be applied on certain boundary parameters. Results. Numerical applications on free vibrated structures are presented to show the efficiency of the developed strategy. When considering a required reliability level, the resulting topology represents a different topology relative to the deterministic resulting one. Discussion and Conclusion. In addition to its simplified implementation, the developed inverse optimum safety factor strategy can be considered as a generative tool to provide the designer with several solutions for free vibrated structures with different performance levels.
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Justification of dual-level opener parameters in digital twin by the discrete element method
Статья научная
Introduction. The discrete element method is the most promising method for modeling soil tillage. With the use of DEM modeling it is possible to create a digital twin for technological process of interaction of tools with soil, analyze the operation of tillage and seeding machines having various design and technological parameters, and predict energy and agrotechnical indicators of еtheir work. To improve the prediction accuracy, it is necessary to compare the obtained data with the results of field experiments. Aim of the Study. The study is aimed at developing a digital twin of the tillage bin through using the discrete element method and optimizing the main design and technological parameters of the dual-level opener.
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Light and temperature control for greenhouse plant growth
Статья научная
Introduction. The article deals with the conditions for growing greenhouse plants. Supplementary lighting supports the process of plant photosynthesis and the microclimate in the greenhouse. The authors suggest the ways to reduce energy consumption in greenhouses by controlling the microclimate and process of supplementary lighting in greenhouses. Materials and Methods. Special lighting and temperature are required for growing greenhouse plants. A method of efficient plant growing is light and temperature control. The development of a control algorithm requires the mathematical models that relate the process of photosynthesis to the microclimate parameters. There are given the mathematical models based on the experimental data. Results. The control system and algorithm to control plant-growing conditions have been developed to maintain the greenhouse microclimate. LED lamps are used to control the lighting process. The authors present the developed block diagram of the control system, which contains four channels responsible for the main energy-intensive microclimate factors. The description of the algorithm of the greenhouse light-temperature control is given. Discussion and Conclusion. In conclusion, the need to maintain the greenhouse microclimate and supplementary lighting with the different radiation spectrum for the efficient cultivation of greenhouse plants is shown. The developed structure and control algorithm for the supplementary plant lighting process and greenhouse illumination through using LED lamps help reduce energy consumption.
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Magnetic bacteria and their potential applications: a review article
Статья научная
Introduction. This outline explores the scientific discovery concerning the magnetotac-tic bacteria (MTB). The results of the discovery are used in microbiology, mineralogy, limnology, physics, biophysics, chemistry, biochemistry, geology, crystallography, and astrobiology. Magnetosomes of the MTB are organized in linear chains and orient the cell body along geomagnetic field lines while flagella actively propel the cells, resulting in so-called magnetotaxis. Materials and Methods. The review article about the magnetotactic bacteria is a collection of many research papers from different institutes. The emerging important points about this review lie in: (1) any biological system is capable of producing magnetic biomaterials such as magnetite (Fe3O4) and gregite (Fe3S4); (2) the navigation of these nano-crystals in the biological system is interconnected with the Earth's magnetic field. Results. The researchers involved in the study have shown that the magnetotactic bacteria do respond to a magnetic field. This makes them attractive for biomedical and industrial applications because of the availability of superior electromagnets, superconducting magnets and permanent magnet. Magnetic bacteria can also be used as a diagnostic tool in the detection of imperfections even at the nanoscale. Discussion and Conclusions. Although the importance of this issue is still limitedly used in medical area, more performance is necessary to explore the world of these bacteria that are candidate for new industry and new therapy strategies in biotechnology and medical fields.
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Method of relative magnitudes for calculating magnetic fluxes in electrical machine
Статья научная
Introduction. The article presents the study results of the model of an asynchronous electric motor carried out by the author within the framework of the Priorities Research Program "Research and development in the priority areas of development of Russia's scientific and technical complex for 2014-2020". Materials and Methods. A model of an idealized asynchronous machine (with sinusoidal distribution of magnetic induction in air gap) is used in vector control systems. It is impossible to create windings for this machine. The basis of the new calculation approach was the Conductivity of Teeth Contours Method, developed at the Electrical Machines Chair of the Moscow Power Engineering Institute (MPEI). Unlike this method, the author used not absolute values, but relative magnitudes of magnetic fluxes. This solution fundamentally improved the method's capabilities. The relative magnitudes of the magnetic fluxes of the teeth contours do not required the additional consideration for exact structure of magnetic field of tooth and adjacent slots. These structures are identical for all the teeth of the machine and differ only in magnitude. The purpose of the calculations was not traditional harmonic analysis of magnetic induction distribution in air gap of machine, but a refinement of the equations of electric machine model. The vector control researchers used only the cos(6) function as a value of mutual magnetic coupling coefficient between the windings. Results. The author has developed a way to take into account the design of the windings of a real machine by using imaginary measuring winding with the same winding design as a real phase winding. The imaginary winding can be placed in the position of any machine windings. The calculation of the relative magnetic fluxes of this winding helped to estimate the real values of the magnetic coupling coefficients between the windings, and find the correction functions for the model of an idealized machine. Modeling in the MATLAB showed that the refinement model of the idealized machine makes the electromagnetic processes similar to the processes of the real machine. Discussion and Conclusions. The use of the proposed correction functions does not require the alteration of the vector control systems. The correction functions make the Park's and Clark's transformations more exact. The model of machine becomes more accurate and the processes taking place inside it coincide with real machine processes. The control of the electric machine becomes more precise.
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Mulch and irrigation effects on tomato performance and weed infestation
Статья научная
The experiment was conducted at the Bangabandhu Sheikh Mujibur Rahman Agricultural University research farm, Gazipur, Bangladesh during November 2008 to March 2009 for determining the effects of irrigation and mulch on the performance of tomato. The experiment was laid out in a split-plot design with three replications where mulch materials (Senna leaf, rice straw and no-mulch) were assigned in main plots, while five irrigation levels (IW/CEP 1.0, IW/CEP 0.75, IW/CEP 0.50, IW/CEP 0.25, and IW/CEP 0.0) were distributed in subplots. Senna leaf mulch gave 4.64 % and 25.02% higher tomato yield than rice straw and no mulch treatment, respectively. IW/CPE 1.0 produced 5.64 %, 13.40 %, 33.04 %, and 87.65 % more yield compared to IW/CPE 0.75, 0.50, 0.25 and no irrigation levels, respectively. Senna leaf mulch with IW/CPE 1.0 level of irrigation produced the highest (58.54 t ha -1) yield, which did not vary significantly with rice straw with IW/CPE 1.0 (56.89 t ha -1) and Senna leaf mulch with IW/CPE 0.75 (56.73 t ha -1). Reducing sugar, total sugar and ascorbic acid were increased with the decreasing irrigation levels, but в carotene increased with increasing irrigation levels. Weed was suppressed significantly under mulch materials than no mulch treatment. Therefore, Senna leaf could be used as potential mulch material for soil moisture conservation, higher tomato yield and weed suppression. About 26 % irrigation water could be saved without significant yield loss if Senna leaf is used as mulch.
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Musculus soleus крыс при физической нагрузке и действии L-карнитина и креатинфосфата
Статья научная
Введение. Исследование влияния препаратов метаболического типа действия на гистохимические характеристики камбаловидной мышцы является актуальным в рамках решения задачи по обеспечению тренировочного процесса в Российской Федерации не допинговыми лекарственными препаратами с целью безопасной коррекции последствий интенсивной физической нагрузки у атлетов. Материалы и методы. Динамическую физическую нагрузку у крыс (n = 24) моделировали плаванием «до отказа» с отягощением 10 % от массы тела (20 сут. 1 раз/день). Подопытные животные были распределены на 4 группы (по 6 особей в каждой): № 1 - интактный контроль, № 2 - плавание + изотонический раствор NaCl, № 3 и № 4 - плавание + соответственно L-карнитин и креатинфосфат по 100,0 мг/кг ежедневно однократно внутрибрюшинно. Объектом исследования служили камбало-видные мышцы (m. soleus). Типирование мышечных волокон проводили по выраженности гистохимической активности сукцинатдегидрогеназы (СДГ) и щелочестабиль-ной аденозинтрифосфотазы (АТФ-азы) миозина. Оценивали процентное содержание мышечных волокон и методом прямой морфометрии определяли их диаметр. Полученные данные обрабатывали статистически с помощью t-критерия Стьюдента. Результаты исследования. Плавание животных «до отказа» не оказывает влияния на соотношение волокон с различными фенотипами в составе камбаловидной мышцы. Данный показатель является генетически детерминированным и не модифицируется L-карнитином и креатинфосфатом. Динамическая физическая нагрузка способствует развитию гипертрофии мышечных волокон различного типа. Исследуемые препараты метаболического типа действия либо не оказывают влияния на формирование гипертрофии, обусловленной физической нагрузкой (в большей степени креатинфосфат) либо уменьшают выраженность гипертрофии (в большей степени L-карнитин) в условиях динамической физической нагрузки. Обсуждение и заключения. Полученные данные свидетельствуют, что L-карнитин и креатинфосфат при длительности применения в 20 сут. не обладают анаболическим эффектом в отношении камбаловидной мышцы. С учетом данных литературы об их способности эффективно корригировать ряд негативных последствий интенсивных физических нагрузок у атлетов, они могут рассматриваться в качестве средств помощи спортсменам различного уровня как лекарственные средства, не обладающие анаболическими свойствами.
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Possibilities of obtaining biogas from manure and amaranth
Статья научная
Introduction. The use of biomass allows increasing the rate of biogas formation and its specific yield. This work aims to study the kinetics of methanogenesis and determine the optimal duration of digestion and organic load, which are the main indicators of the technological process of biogas formation. Materials and Methods. The substrate (dairy manure, biomass of amaranth) was the study object. Experimental studies were carried out using a laboratory biogas plant. The computer program (certificate No. 2018662045) was used to obtain modified Gompertz models describing the kinetics of biogas formation. Based on the obtained data, the hydraulic retention time and organic loading rate (the key parameters in the design of biogas plants were determined). Results. The paper presents the experimental studies results of the biogas formation kinetics when using dry amaranth biomass. The Gompertz mathematical models were obtained. Methane-tank control parameters (hydraulic retention time and organic loading rate) were obtained for anaerobic digestion of a new substrate. Discussion and Conclusion. The use of new co-substrate Amaranthus retroflexus L. allowed increasing the specific biogas yield from dairy manure by 52.2 % and the ultrasonic pre-treatment in combination with the herbal supplement by 89.1 %. The optimal hydraulic retention time value was 10 days and organic loading rate was 4.1 kg of volatile solids per m3 of digester per day.
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Power analysis of toroidal core electromagnetic energy harvesters for transmission lines
Статья научная
Introduction. As the need for energy increases, energy harvesting methods have also been intensively researched. Energy harvesting techniques which are a way of converting low amounts of energy from the environment into electrical energy can be used to meet the energy needs of low-power electronic devices and sensors. The increase in such sensors and devices with low power consumption also makes energy harvesting techniques more important. One of these harvesting techniques is energy harvesting from electromagnetic fields, which is obtained from transmission lines. Aim of the Article. The article is aimed at developing an effective electromagnetic energy harvester from energy transmission lines for unmanned aerial vehicles.
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Статья научная
Introduction. The Deterministic Topology Optimization model provides a single solution for a given design space, while the Reliability-Based Topology Optimization model provides several reliability-based topology layouts with high-performance levels. The objective of this work is to develop two strategies that can provide the designer with two categories of resulting topologies. Materials and Methods. Two alternative approaches based on the Inverse Optimum Safety Factor are developed: the first one is called the Objective-Based IOSF Approach and the second one is called Performance-Based IOSF Approach. When dealing with bridge structures, the uncertainty on the input parameters (boundary conditions, material properties, geometry, etc.) and also output parameters (compliance, etc.) should not be ignored. The sensitivity analysis is the fundamental idea of both developed approaches, identifies the role of each parameter on the structural performance. In addition, the optimization domain choice is important when eliminating material that should not affect the structure functioning. Results. Two numerical examples on a 2D bridge structure are presented to demonstrate the efficiency of the developed approaches. When considering a certain reliability level, the Reliability-Based Topology Optimization leads to two different configurations relative to the Deterministic Topology Optimization one. When increasing the reliability levels, the quantity of materials decreases that leads to an increase in the number of holes in the structures. Discussion and Conclusion. In addition to their simplified implementation, the developed alternative approaches can be considered as two generative tools to produce two different categories (families) of solutions where an alternative choice between two functions (objective/performance) is presented.
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